2 // field.cs: All field handlers
4 // Authors: Miguel de Icaza (miguel@gnu.org)
5 // Martin Baulig (martin@ximian.com)
6 // Marek Safar (marek.safar@seznam.cz)
8 // Dual licensed under the terms of the MIT X11 or GNU GPL
10 // Copyright 2001, 2002, 2003 Ximian, Inc (http://www.ximian.com)
11 // Copyright 2004-2008 Novell, Inc
12 // Copyright 2011 Xamarin Inc
16 using System.Collections.Generic;
17 using System.Runtime.InteropServices;
20 using MetaType = IKVM.Reflection.Type;
21 using IKVM.Reflection;
22 using IKVM.Reflection.Emit;
24 using MetaType = System.Type;
25 using System.Reflection;
26 using System.Reflection.Emit;
31 public class FieldDeclarator
33 public FieldDeclarator (SimpleMemberName name, Expression initializer)
36 this.Initializer = initializer;
41 public SimpleMemberName Name { get; private set; }
42 public Expression Initializer { get; private set; }
46 public virtual FullNamedExpression GetFieldTypeExpression (FieldBase field)
48 return new TypeExpression (field.MemberType, Name.Location);
53 // Abstract class for all fields
55 abstract public class FieldBase : MemberBase
57 protected FieldBuilder FieldBuilder;
58 protected FieldSpec spec;
60 protected Expression initializer;
61 protected List<FieldDeclarator> declarators;
64 public enum Status : byte {
65 HAS_OFFSET = 4 // Used by FieldMember.
68 static readonly string[] attribute_targets = new string [] { "field" };
70 protected FieldBase (TypeDefinition parent, FullNamedExpression type, Modifiers mod, Modifiers allowed_mod, MemberName name, Attributes attrs)
71 : base (parent, type, mod, allowed_mod | Modifiers.ABSTRACT, Modifiers.PRIVATE, name, attrs)
73 if ((mod & Modifiers.ABSTRACT) != 0)
74 Report.Error (681, Location, "The modifier 'abstract' is not valid on fields. Try using a property instead");
79 public override AttributeTargets AttributeTargets {
81 return AttributeTargets.Field;
85 public List<FieldDeclarator> Declarators {
87 return this.declarators;
91 public Expression Initializer {
96 this.initializer = value;
102 return MemberName.Name;
106 public FieldSpec Spec {
112 public override string[] ValidAttributeTargets {
114 return attribute_targets;
120 public void AddDeclarator (FieldDeclarator declarator)
122 if (declarators == null)
123 declarators = new List<FieldDeclarator> (2);
125 declarators.Add (declarator);
127 Parent.AddNameToContainer (this, declarator.Name.Value);
130 public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
132 if (a.Type == pa.FieldOffset) {
133 status |= Status.HAS_OFFSET;
135 if (!Parent.PartialContainer.HasExplicitLayout) {
136 Report.Error (636, Location, "The FieldOffset attribute can only be placed on members of types marked with the StructLayout(LayoutKind.Explicit)");
140 if ((ModFlags & Modifiers.STATIC) != 0 || this is Const) {
141 Report.Error (637, Location, "The FieldOffset attribute is not allowed on static or const fields");
146 if (a.Type == pa.FixedBuffer) {
147 Report.Error (1716, Location, "Do not use 'System.Runtime.CompilerServices.FixedBuffer' attribute. Use the 'fixed' field modifier instead");
152 if (a.Type == pa.MarshalAs) {
153 UnmanagedMarshal marshal = a.GetMarshal (this);
154 if (marshal != null) {
155 FieldBuilder.SetMarshal (marshal);
160 if ((a.HasSecurityAttribute)) {
161 a.Error_InvalidSecurityParent ();
165 if (a.Type == pa.Dynamic) {
166 a.Error_MisusedDynamicAttribute ();
170 FieldBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), cdata);
173 public void SetCustomAttribute (MethodSpec ctor, byte[] data)
175 FieldBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), data);
178 protected override bool CheckBase ()
180 if (!base.CheckBase ())
183 MemberSpec candidate;
184 bool overrides = false;
185 var conflict_symbol = MemberCache.FindBaseMember (this, out candidate, ref overrides);
186 if (conflict_symbol == null)
187 conflict_symbol = candidate;
189 if (conflict_symbol == null) {
190 if ((ModFlags & Modifiers.NEW) != 0) {
191 Report.Warning (109, 4, Location, "The member `{0}' does not hide an inherited member. The new keyword is not required",
192 GetSignatureForError ());
195 if ((ModFlags & (Modifiers.NEW | Modifiers.OVERRIDE | Modifiers.BACKING_FIELD)) == 0) {
196 Report.SymbolRelatedToPreviousError (conflict_symbol);
197 Report.Warning (108, 2, Location, "`{0}' hides inherited member `{1}'. Use the new keyword if hiding was intended",
198 GetSignatureForError (), conflict_symbol.GetSignatureForError ());
201 if (conflict_symbol.IsAbstract) {
202 Report.SymbolRelatedToPreviousError (conflict_symbol);
203 Report.Error (533, Location, "`{0}' hides inherited abstract member `{1}'",
204 GetSignatureForError (), conflict_symbol.GetSignatureForError ());
211 public virtual Constant ConvertInitializer (ResolveContext rc, Constant expr)
213 return expr.ConvertImplicitly (MemberType);
216 protected override void DoMemberTypeDependentChecks ()
218 base.DoMemberTypeDependentChecks ();
220 if (MemberType.IsGenericParameter)
223 if (MemberType.IsStatic)
224 Error_VariableOfStaticClass (Location, GetSignatureForError (), MemberType, Report);
231 // Represents header string for documentation comment.
233 public override string DocCommentHeader {
237 public override void Emit ()
239 if (member_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic) {
240 Module.PredefinedAttributes.Dynamic.EmitAttribute (FieldBuilder);
241 } else if (!Parent.IsCompilerGenerated && member_type.HasDynamicElement) {
242 Module.PredefinedAttributes.Dynamic.EmitAttribute (FieldBuilder, member_type, Location);
245 if ((ModFlags & Modifiers.COMPILER_GENERATED) != 0 && !Parent.IsCompilerGenerated)
246 Module.PredefinedAttributes.CompilerGenerated.EmitAttribute (FieldBuilder);
247 if ((ModFlags & Modifiers.DEBUGGER_HIDDEN) != 0)
248 Module.PredefinedAttributes.DebuggerBrowsable.EmitAttribute (FieldBuilder, System.Diagnostics.DebuggerBrowsableState.Never);
250 if (OptAttributes != null) {
251 OptAttributes.Emit ();
254 if (((status & Status.HAS_OFFSET) == 0) && (ModFlags & (Modifiers.STATIC | Modifiers.BACKING_FIELD)) == 0 && Parent.PartialContainer.HasExplicitLayout) {
255 Report.Error (625, Location, "`{0}': Instance field types marked with StructLayout(LayoutKind.Explicit) must have a FieldOffset attribute", GetSignatureForError ());
258 ConstraintChecker.Check (this, member_type, type_expr.Location);
263 public static void Error_VariableOfStaticClass (Location loc, string variable_name, TypeSpec static_class, Report Report)
265 Report.SymbolRelatedToPreviousError (static_class);
266 Report.Error (723, loc, "`{0}': cannot declare variables of static types",
270 protected override bool VerifyClsCompliance ()
272 if (!base.VerifyClsCompliance ())
275 if (!MemberType.IsCLSCompliant () || this is FixedField) {
276 Report.Warning (3003, 1, Location, "Type of `{0}' is not CLS-compliant",
277 GetSignatureForError ());
284 // Field specification
286 public class FieldSpec : MemberSpec, IInterfaceMemberSpec
291 public FieldSpec (TypeSpec declaringType, IMemberDefinition definition, TypeSpec memberType, FieldInfo info, Modifiers modifiers)
292 : base (MemberKind.Field, declaringType, definition, modifiers)
294 this.metaInfo = info;
295 this.memberType = memberType;
300 public bool IsReadOnly {
302 return (Modifiers & Modifiers.READONLY) != 0;
306 public TypeSpec MemberType {
314 public FieldInfo GetMetaInfo ()
316 if ((state & StateFlags.PendingMetaInflate) != 0) {
317 var decl_meta = DeclaringType.GetMetaInfo ();
318 if (DeclaringType.IsTypeBuilder) {
319 metaInfo = TypeBuilder.GetField (decl_meta, metaInfo);
321 var orig_token = metaInfo.MetadataToken;
322 metaInfo = decl_meta.GetField (Name, BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static);
323 if (metaInfo.MetadataToken != orig_token)
324 throw new NotImplementedException ("Resolved to wrong meta token");
326 // What a stupid API, does not work because field handle is imported
327 // metaInfo = FieldInfo.GetFieldFromHandle (metaInfo.FieldHandle, DeclaringType.MetaInfo.TypeHandle);
330 state &= ~StateFlags.PendingMetaInflate;
336 public override MemberSpec InflateMember (TypeParameterInflator inflator)
338 var fs = (FieldSpec) base.InflateMember (inflator);
339 fs.memberType = inflator.Inflate (memberType);
343 public FieldSpec Mutate (TypeParameterMutator mutator)
345 var decl = DeclaringType;
346 if (DeclaringType.IsGenericOrParentIsGeneric)
347 decl = mutator.Mutate (decl);
349 if (decl == DeclaringType)
352 var fs = (FieldSpec) MemberwiseClone ();
353 fs.declaringType = decl;
354 fs.state |= StateFlags.PendingMetaInflate;
356 // Gets back FieldInfo in case of metaInfo was inflated
357 fs.metaInfo = MemberCache.GetMember (TypeParameterMutator.GetMemberDeclaringType (DeclaringType), this).metaInfo;
361 public override List<TypeSpec> ResolveMissingDependencies ()
363 return memberType.ResolveMissingDependencies ();
368 /// Fixed buffer implementation
370 public class FixedField : FieldBase
372 public const string FixedElementName = "FixedElementField";
373 static int GlobalCounter = 0;
375 TypeBuilder fixed_buffer_type;
377 const Modifiers AllowedModifiers =
380 Modifiers.PROTECTED |
385 public FixedField (TypeDefinition parent, FullNamedExpression type, Modifiers mod, MemberName name, Attributes attrs)
386 : base (parent, type, mod, AllowedModifiers, name, attrs)
393 // Explicit struct layout set by parent
395 public CharSet? CharSet {
401 public override Constant ConvertInitializer (ResolveContext rc, Constant expr)
403 return expr.ImplicitConversionRequired (rc, rc.BuiltinTypes.Int, Location);
406 public override bool Define ()
411 if (!BuiltinTypeSpec.IsPrimitiveType (MemberType)) {
412 Report.Error (1663, Location,
413 "`{0}': Fixed size buffers type must be one of the following: bool, byte, short, int, long, char, sbyte, ushort, uint, ulong, float or double",
414 GetSignatureForError ());
415 } else if (declarators != null) {
416 foreach (var d in declarators) {
417 var f = new FixedField (Parent, d.GetFieldTypeExpression (this), ModFlags, new MemberName (d.Name.Value, d.Name.Location), OptAttributes);
418 f.initializer = d.Initializer;
419 ((ConstInitializer) f.initializer).Name = d.Name.Value;
421 Parent.PartialContainer.Members.Add (f);
425 // Create nested fixed buffer container
426 string name = String.Format ("<{0}>__FixedBuffer{1}", Name, GlobalCounter++);
427 fixed_buffer_type = Parent.TypeBuilder.DefineNestedType (name,
428 TypeAttributes.NestedPublic | TypeAttributes.Sealed | TypeAttributes.BeforeFieldInit,
429 Compiler.BuiltinTypes.ValueType.GetMetaInfo ());
431 var ffield = fixed_buffer_type.DefineField (FixedElementName, MemberType.GetMetaInfo (), FieldAttributes.Public);
433 FieldBuilder = Parent.TypeBuilder.DefineField (Name, fixed_buffer_type, ModifiersExtensions.FieldAttr (ModFlags));
435 var element_spec = new FieldSpec (null, this, MemberType, ffield, ModFlags);
436 spec = new FixedFieldSpec (Module, Parent.Definition, this, FieldBuilder, element_spec, ModFlags);
438 Parent.MemberCache.AddMember (spec);
442 protected override void DoMemberTypeIndependentChecks ()
444 base.DoMemberTypeIndependentChecks ();
447 Expression.UnsafeError (Report, Location);
449 if (Parent.PartialContainer.Kind != MemberKind.Struct) {
450 Report.Error (1642, Location, "`{0}': Fixed size buffer fields may only be members of structs",
451 GetSignatureForError ());
455 public override void Emit()
457 ResolveContext rc = new ResolveContext (this);
458 IntConstant buffer_size_const = initializer.Resolve (rc) as IntConstant;
459 if (buffer_size_const == null)
462 int buffer_size = buffer_size_const.Value;
464 if (buffer_size <= 0) {
465 Report.Error (1665, Location, "`{0}': Fixed size buffers must have a length greater than zero", GetSignatureForError ());
469 EmitFieldSize (buffer_size);
472 if (Module.HasDefaultCharSet)
473 fixed_buffer_type.__SetAttributes (fixed_buffer_type.Attributes | Module.DefaultCharSetType);
476 Module.PredefinedAttributes.UnsafeValueType.EmitAttribute (fixed_buffer_type);
477 Module.PredefinedAttributes.CompilerGenerated.EmitAttribute (fixed_buffer_type);
478 fixed_buffer_type.CreateType ();
483 void EmitFieldSize (int buffer_size)
485 int type_size = BuiltinTypeSpec.GetSize (MemberType);
487 if (buffer_size > int.MaxValue / type_size) {
488 Report.Error (1664, Location, "Fixed size buffer `{0}' of length `{1}' and type `{2}' exceeded 2^31 limit",
489 GetSignatureForError (), buffer_size.ToString (), MemberType.GetSignatureForError ());
493 AttributeEncoder encoder;
495 var ctor = Module.PredefinedMembers.StructLayoutAttributeCtor.Resolve (Location);
499 var field_size = Module.PredefinedMembers.StructLayoutSize.Resolve (Location);
500 var field_charset = Module.PredefinedMembers.StructLayoutCharSet.Resolve (Location);
501 if (field_size == null || field_charset == null)
504 var char_set = CharSet ?? Module.DefaultCharSet ?? 0;
506 encoder = new AttributeEncoder ();
507 encoder.Encode ((short)LayoutKind.Sequential);
508 encoder.EncodeNamedArguments (
509 new [] { field_size, field_charset },
511 new IntConstant (Compiler.BuiltinTypes, buffer_size * type_size, Location),
512 new IntConstant (Compiler.BuiltinTypes, (int) char_set, Location)
516 fixed_buffer_type.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), encoder.ToArray ());
519 // Don't emit FixedBufferAttribute attribute for private types
521 if ((ModFlags & Modifiers.PRIVATE) != 0)
524 ctor = Module.PredefinedMembers.FixedBufferAttributeCtor.Resolve (Location);
528 encoder = new AttributeEncoder ();
529 encoder.EncodeTypeName (MemberType);
530 encoder.Encode (buffer_size);
531 encoder.EncodeEmptyNamedArguments ();
533 FieldBuilder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), encoder.ToArray ());
537 class FixedFieldSpec : FieldSpec
539 readonly FieldSpec element;
541 public FixedFieldSpec (ModuleContainer module, TypeSpec declaringType, IMemberDefinition definition, FieldInfo info, FieldSpec element, Modifiers modifiers)
542 : base (declaringType, definition, PointerContainer.MakeType (module, element.MemberType), info, modifiers)
544 this.element = element;
546 // It's never CLS-Compliant
547 state &= ~StateFlags.CLSCompliant_Undetected;
550 public FieldSpec Element {
556 public TypeSpec ElementType {
558 return element.MemberType;
564 // The Field class is used to represents class/struct fields during parsing.
566 public class Field : FieldBase {
568 // Modifiers allowed in a class declaration
570 const Modifiers AllowedModifiers =
573 Modifiers.PROTECTED |
581 public Field (TypeDefinition parent, FullNamedExpression type, Modifiers mod, MemberName name, Attributes attrs)
582 : base (parent, type, mod, AllowedModifiers, name, attrs)
586 bool CanBeVolatile ()
588 switch (MemberType.BuiltinType) {
589 case BuiltinTypeSpec.Type.Bool:
590 case BuiltinTypeSpec.Type.Char:
591 case BuiltinTypeSpec.Type.SByte:
592 case BuiltinTypeSpec.Type.Byte:
593 case BuiltinTypeSpec.Type.Short:
594 case BuiltinTypeSpec.Type.UShort:
595 case BuiltinTypeSpec.Type.Int:
596 case BuiltinTypeSpec.Type.UInt:
597 case BuiltinTypeSpec.Type.Float:
598 case BuiltinTypeSpec.Type.UIntPtr:
599 case BuiltinTypeSpec.Type.IntPtr:
603 if (TypeSpec.IsReferenceType (MemberType))
606 if (MemberType.IsEnum)
612 public override void Accept (StructuralVisitor visitor)
614 visitor.Visit (this);
617 public override bool Define ()
622 MetaType[] required_modifier = null;
623 if ((ModFlags & Modifiers.VOLATILE) != 0) {
624 var mod = Module.PredefinedTypes.IsVolatile.Resolve ();
626 required_modifier = new MetaType[] { mod.GetMetaInfo () };
629 FieldBuilder = Parent.TypeBuilder.DefineField (
630 Name, member_type.GetMetaInfo (), required_modifier, null, ModifiersExtensions.FieldAttr (ModFlags));
632 spec = new FieldSpec (Parent.Definition, this, MemberType, FieldBuilder, ModFlags);
635 // Don't cache inaccessible fields except for struct where we
636 // need them for definitive assignment checks
638 if ((ModFlags & Modifiers.BACKING_FIELD) == 0 || Parent.Kind == MemberKind.Struct) {
639 Parent.MemberCache.AddMember (spec);
642 if (initializer != null) {
643 Parent.RegisterFieldForInitialization (this, new FieldInitializer (this, initializer, TypeExpression.Location));
646 if (declarators != null) {
647 foreach (var d in declarators) {
648 var f = new Field (Parent, d.GetFieldTypeExpression (this), ModFlags, new MemberName (d.Name.Value, d.Name.Location), OptAttributes);
649 if (d.Initializer != null)
650 f.initializer = d.Initializer;
653 Parent.PartialContainer.Members.Add (f);
660 protected override void DoMemberTypeDependentChecks ()
662 if ((ModFlags & Modifiers.BACKING_FIELD) != 0)
665 base.DoMemberTypeDependentChecks ();
667 if ((ModFlags & Modifiers.VOLATILE) != 0) {
668 if (!CanBeVolatile ()) {
669 Report.Error (677, Location, "`{0}': A volatile field cannot be of the type `{1}'",
670 GetSignatureForError (), MemberType.GetSignatureForError ());
673 if ((ModFlags & Modifiers.READONLY) != 0) {
674 Report.Error (678, Location, "`{0}': A field cannot be both volatile and readonly",
675 GetSignatureForError ());
680 protected override bool VerifyClsCompliance ()
682 if (!base.VerifyClsCompliance ())
685 if ((ModFlags & Modifiers.VOLATILE) != 0) {
686 Report.Warning (3026, 1, Location, "CLS-compliant field `{0}' cannot be volatile", GetSignatureForError ());